could sub
Verbe régulier : sub - subbed- subbed
Traduction française : substituer - remplacer 

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I could sub
you could sub
she could sub
we could sub
you could sub
they could sub 	I could be subbing
you could be subbing
she could be subbing
we could be subbing
you could be subbing
they could be subbing	I could have subbed
you could have subbed
she could have subbed
we could have subbed
you could have subbed
they could have subbed	I could have been subbing
you could have been subbing
she could have been subbing
we could have been subbing
you could have been subbing
they could have been subbing	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I could not sub
you could not sub
she could not sub
we could not sub
you could not sub
they could not sub 	I could not be subbing
you could not be subbing
she could not be subbing
we could not be subbing
you could not be subbing
they could not be subbing	I could not have subbed
you could not have subbed
she could not have subbed
we could not have subbed
you could not have subbed
they could not have subbed	I could not have been subbing
you could not have been subbing
she could not have been subbing
we could not have been subbing
you could not have been subbing
they could not have been subbing	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
could I sub?
could you sub?
could she sub?
could we sub?
could you sub?
could they sub? 	could I be subbing?
could you be subbing?
could she be subbing?
could we be subbing?
could you be subbing?
could they be subbing? 	could I have subbed?
could you have subbed?
could she have subbed?
could we have subbed?
could you have subbed?
could they have subbed? 	could I have been subbing?
could you have been subbing?
could she have been subbing?
could we have been subbing?
could you have been subbing?
could they have been subbing? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
could I not sub?
could you not sub?
could she not sub?
could we not sub?
could you not sub?
could they not sub? 	could I not be subbing?
could you not be subbing?
could she not be subbing?
could we not be subbing?
could you not be subbing?
could they not be subbing? 	could I not have subbed?
could you not have subbed?
could she not have subbed?
could we not have subbed?
could you not have subbed?
could they not have subbed? 	could I not have been subbing?
could you not have been subbing?
could she not have been subbing?
could we not have been subbing?
could you not have been subbing?
could they not have been subbing?